Personal devices are known that allow a user to store data in the device for the purpose of providing the data to external systems. For example, such personal devices include credit card consolidators that store multiple credit card numbers, and that allow a user to select one of the credit cards for making payment at a point of sale. A magnetic stripe emulator is used by such devices to provide the selected credit card number to a magnetic stripe reader.
While such devices allow multiple credit card numbers and related information to be stored, they present an increased risk from theft of the device, because they allow an unauthorized user can still bypass security measures. For example, if a PIN number is required by the device, an unauthorized user would be able to try various PIN numbers until one was found that worked. Such devices also provide limited additional functionality.